Screen for centrifugal baskets



Q 1 1927. P" 9 E. ROBERTS SCREEN FOR CENTRIFUGAL BASKETS Filed Aug. 18. 1921 Patented Apr. 19,1921.

UNITED STATES EUGENE ROBERTS, 0E SALT LAKE CITY, UTAH, AssIeNoE To THE WESTERN STATES MACHINE COMPANY, or SALT LAKE CITY, UTAH, A CORPQRATIQN or JTAII.

The present invention deals with the problem of maintenance ofthe perforated screens or linings of centrifugal separators used in the separation or extraction of the liquid content from the solid matter as exemplified exceedingly heavy particularly near the bottom of the basket where there is the greatest accumulation of the massed sugar. This excessive pressure greatly increasing toward the bottom of the basket results in an actual stretching of the screen which is greatest near the bottom, thereby tending to give the screen a slight thrust roll conical form with the greatest diameter at the base. As the screen is externally supported by the cylindrical basket Wall and the interposed or intermediate reticulatedbacking, such stretching tends to cause the screen to buckle or 2 wrinkle so that injury is caused when the sugar-discharging .plow is brought into working contact with the interior face of the perforated screen as the basket is rotated v in the operation of removing the walled-up sugar. 4,

The prevention of such buckling or wrinklinghproducing unevenness in the screen and lea 'ng to rapid deterioration of these expensive parts is the object of the present Invention. In my former Patent 1,300,486, dated April 15, 1919 there was disclosed a form of joint for centrifugal basket screens intended to prevent the spreading apart or separating of the overlapped ends of a centrifugal basket screen, but while this. joint accomplishes its purpose of keeping the overlapped edges of the screen close together, it does not prevent the stretching of the screen under the outward pressure of the sugar mass whereby the screen is gradually caused to assume the thrust roll conical shape which preventsoit from properly fit tin the intermediate of the cylindrical bas et Wall which leads to buckling and ing or screen in a plurality of separate sections having their overlapped end edges SCREEN FOR CENTRIFUGAII BASKETS.

.Application-filed August 1a, 1921. Serial 493,354. v

joined together by an cxpansible joint from top to bottom whereby both the upper and equally but without buckling or formation of ridges or wrinkles in the screen itself in order that-the screcn ma'y' be self-adjusting no matter how great-the internal pressure so that it will always preserve the cylindrical form and thus lie smoothly against the interior of the cylindrical basket wall of the interposed reticulated backingv the lower portions of the screens may stretch In the accompanying drawings I have illustrated a form of constructionembodying f the principles of this invention in which:

Figure 1 is a perspective view'showing the multi-part screen inside the perforated basket, the front portion of the basket of the reticulated lining being broken away to show the front half of the screen. v

Figure 2 is a flat development showing two sections of the screen united together by a lap joint such as illustrated in my afore-- said Letters Patent.

Figure 3 is a detail of the screen in cross section on the horizontal plane intersecting the external series of overlapping tongues.

In the practice of this invention, according to the form illustrated inthe drawings, I employ a sheet metal screenperforated in accordance with the usual practlce and made up as shown in this case of three sections 4,

or end edge with a series of properly spaced Vertical slots 5. The cooperating or matching adjacent end edge of the next. screen section is slitted circumferentially for a few inches to form a series of tongues 6 narrow enough to be thrust through the slots 5 from the end edge of the adjacent section having I the vertical slots 5 sothat thetwo series of tongues form an overlapping interwoven .or jointedstructure with a serles'of external tongues passing entirely outside of the overlapped portion of the next section and a series ofinserted tongues pass from the .inside out through the slots 5 and overlapping the exterior of the next section.

' The screen when thus assembled is in- 85 each of which is provided. along one vertical Ill serted inside the usual cylindrical basket 1 which is provided with the reenforcing ribs 2, and which also carries an interior reticulated backing 3 to allow the flow of liquid escaping through the screen sections 4 to the perforations in the basket which are larger and more widely separated than the perforations in the screen which latter are indicated at 8, and which extend throughout the screen sections inside of their edges but for convenience are shown only in part.

The screen having been assembled and inserted inside the basket and tacking can then be expanded by hand until its fits perfectly against the surrounding retaining wall formed by the basket or by the backing.

The rapid rotation of the centrifugal basket with its interior mass or sugar tends to expand the lining but has the expansible joints located at intervals around the screen extended from top to bottom. The screen is thus made self-adjusting and is always free under such pressure to seat itself snugly against its surrounding supporting wall and thereby maintain its proper cylindrical form without fold or wrinkle against which the discharger plow may impinge tothe inaniiest in ury of the screen. Any desired number of joints of this type may be used in the screen, but the three joints illustrated in the drawings are suflicient to effectively accomplish the desired purpose and greatly prolong the life of the screen while avoiding also in ury to the plow tip as well.

\Vhat 1 claim is:

l. A screen for a centrifugal basket cmbracing in construction a plurality ofcir- (annferential sections having their opposite ends overlapping the adjacent ends of the next section and joined therewith to prevent lateral separation while allowing circumferentialexpansion, substantially as described.

2. A screen for a centrifugal basket embracing a series of arcuate sections whose adjacent end edges are provided with a 00- operating series of tongues and slots to form interwoven overlapping joints, whereby the arcuate sections may be joined to form a complete cylindrical screen capable of expanding equally at top and bottom so as to preserve its cylindrical form when expanded under the pressure of the interior mass of solid material, substantially as described.

3. A screen for centrifugal baskets embracing a plurality of arcuate sections whose adjacent ends are joined together by circumferentially extensible overlapping oints extending from top to bottom of the screen, substantially as described.

In witness whereof, I have subscribed the above specification.

EUGENE ROBERTS. 

